Are you a six report? Meaning, did you work all five days this week? If not, than you will be paid your regular hourly rate. If this saturday is your 6th day reporting to work, than you will be paid overtime rate regardless of the number of hours earned during the week.
Depends on what your regular job is. I remember reg. temp. drivers who where also air drivers that had to work Saturdays if they did not 37 hours in on their other 5 days that week. Saturday was straight time for them even if they had over time in other days that week.